WASHINGTON - Chances are that about 15 percent of the food you eat - more if your diet includes lots of fruits, vegetables and cheese - comes from abroad, and the government is taking steps now to make it safer.

New rules proposed Friday by the Food and Drug Administration would make U.S. food importers responsible for ensuring that their suppliers are handling and processing food safely.

Imported fruit and cheese has been responsible for many recent outbreaks, including 153 recent hepatitis A illnesses linked to a frozen berry mix sold at Costco as well as four deaths last year that were linked to listeria in Italian cheese. Imported fruits or vegetables are also the top suspect in an ongoing outbreak of cyclosporiasis, a gastrointestinal infection that has so far sickened 321 people in 13 states.

Other illnesses in the last several years have been linked to imported papayas, mangoes, and nuts and spices used as ingredients. An estimated 3,000 people die of food-related illnesses every year.

The proposed rules, required by a sweeping food safety law passed by Congress in 2010, are meant to establish better checks on what long has been a scattershot effort to guard against unsafe food imported from more than 150 countries. Only about 2 percent of that food is inspected by the government at ports and borders.

The guidelines would require U.S. food importers to verify that the foreign companies they are importing from are achieving the same levels of food safety required in this country. The government estimates that the rules, which would also improve audits of food facilities abroad, could eventually cost the food industry up to $472 million annually.

FDA Commissioner Margaret Hamburg used the frozen berry illnesses, linked to pomegranate seeds from Turkey, as an example of an outbreak that could have been prevented if the new rules were in place. She said it illustrates the "growing complexity of the food supply." FDA investigators had to look at berries from several different countries that were included in the mix before they zeroed in on the Turkish seeds.

Hamburg and other FDA officials say the rules show a major shift in thinking in the way the government works to keep food safe.

Like rules for domestic farmers and food companies released earlier this year, the idea is to make businesses more responsible for the safety of the food they are selling or importing by proving they are using good food safety practices. They might do that by documenting basic information about their suppliers' cleanliness, testing foods or acquiring food-safety audits. If they fail to verify the food is safe, the FDA could stop shipments of their food.

Currently, the government does little to ensure that companies are trying to prevent food safety problems but generally waits and responds to outbreaks after they happen.

FDA regulators say the new rules are necessary as the food system becomes more complex and more global. Food often stops in several locations and passes through many different hands in a matter of days before it hits grocery shelves. And a lack of funding has given the FDA little oversight over what is being produced. The agency inspects most food companies in the United States only every five to 10 years, and it does even fewer inspections abroad.

The food-safety law requires the agency to step up those foreign inspections, which jumped from 300 facilities in 2010 to 1,300 last year, according to the FDA. But that is still a just a fraction of the companies that import to the United States.

The import safety proposal doesn't include oversight for meat, which is mostly produced domestically and is regulated by the Agriculture Department, or seafood, which is already subject to regulations on import safety. About 80 percent of the seafood Americans eat is imported.

The rules would also exempt smaller importers that have less than $500,000 in sales annually.

The domestic food-safety rules proposed in January would require U.S. farms and food processors to take new precautions against contamination such as making sure workers' hands are washed, irrigation water is clean and livestock stay out of fields. Food manufacturers will have to submit food- safety plans to show they are keeping their operations clean.

The food industry, aware of the toll major outbreaks can have on sales, has been supportive of the FDA food-safety proposals and worked with Congress to pass the law three years ago.